Obstruction of the upper airway by the tongue is a common complication when a sedated or unconscious patient is lying in the supine position. The causes of unconsciousness may be sedation, anesthesia, head trauma, drug overdose or any of a multitude of medical causes. The patient may be in any emergency situation. The direct cause is that gravity pulls the person's tongue downwards (towards the cervical spine) and the tongue obstructs the airway and impedes respiration, partially or completely. The airway obstruction discussed above might cause a life-threatening situation if the airway obstruction is not urgently cleared, for hypoxemia and death can quickly ensue.
Anesthesiologists commonly overcome airway obstruction by tilting the patient's head backwards and pulling the chin up towards the ceiling and away from the body (cephalad). Obstruction of the airway is overcome because the base of the tongue is attached to the mandible, and by pulling the chin upward the tongue will be simultaneously pulled upward. This practice is very fatiguing and restricts the anesthesiologist's or emergency responder's ability to perform other functions that require two free hands.
An upper airway can also be maintained open by inserting various medical tubes into the airway, for example, nasal-pharyngeal, oral-pharyngeal, laryngeal mask airway (LMA) and the cuffed oral pharyngeal. But as of today, there are no medical devices in common use that attach externally to the face that will maintain an open upper airway.
In the past, medical personnel have attempted to use surgical tape to attempt to maintain an open upper airway. Anesthesiologist would secure tape around the chin of a patient and then attach the ends of the tape to an operating room table. Tape procedures are unsatisfactory, for the tape attachment pulls back and downwards and do not provide the upward pull required on the chin to maintain an open upper airway. Tape quickly stretches and traction is lost. Tape is not sufficiently adherent to cope with the traction forces and detaches. Other complications with this procedure are skin trauma and eye damage. The tape passes close to the patient's eyes and contact with the eye is unavoidable if the patient coughs or turns the head. The method of attaching tape to the operating room table cannot be used to manage an obstructed airway outside of the operating room, example, at a roadside motor vehicle accident or during subsequent transportation to hospital.
Chin props comprising a ball on the end of an arm secured to the operating room table have also been used to push the chin up. They too have proven to be unsatisfactory and are not commonly used, because they are large and cumbersome and get in the way of surgeons operating on the upper body. Furthermore, if misapplied they may constrict the airway. Chin props with complex mechanisms that attach to suitable operating tables, cannot be used to manage an obstructed airway outside of the operating room, for example, at a roadside motor vehicle accident or during subsequent transportation to hospital.
Information relevant to attempts to address these problems can be found in U.S. Pat. Nos. 5,494,048, 6,200,285 B1, and 6,196,224 B1. However, each one of these references suffers from one or more of the following disadvantages:
1. Can cause eye damage and skin trauma;
2. Require attachment to suitable operating tables;
3. Obstruct the attendant's view of the patient;
4. Do not provide sufficient upward leverage to the chin;
5. Do not lend themselves to use in accident situations;
6. Do not effectively overcome airway obstruction; and
7. Difficulties in removal of devices, should immediate endotracheal intubation be required.
Inside and outside the operating room, an urgent need exists for equipment that overcomes upper airway obstruction and maintains an open upper airway. This equipment should be compatible with and improve the effectiveness of oral-pharyngeal and nasal-pharyngeal airways and face masks. In the operating room, such equipment would allow mask anesthesia to be used for sedated and anesthetized patients instead of general anesthesia and endotracheal intubation with immediate cost savings. Outside the operating room, a need exists for portable, compact equipment that can overcome upper airway obstruction and maintain an open airway and that can be used in cramped quarters such as an ambulance, a hyperbaric chamber and an MRI chamber.
For the foregoing reasons, there is a need for a medical device is safe and reliable that will overcome upper airway obstruction and that will maintain an open airway in the anesthetized and sedated patient lying in a supine position in an operating room and any unconscious patient lying in the supine position at any site. To be effective, the equipment should be safe and easy to use and reliable. The equipment should free up the operators' hands; render oral and nasal pharyngeal airways more effective and not interfere with but facilitate the use of a face mask. The equipment should be free standing, compact and portable.